Abstract: A new method named nomal-equidistant-curve method is presented to generate profile for scroll compressor. Theorem for generating profile is demonstrated. General equation describing geometry of scroll is given. The relationship between type of generatrix and profile of scroll is discussed in detail. Advantages of nomal-equidistant-curve method versus traditional generating method are summarized. The basic re-quirements that generatrix of profiles should meet are expli-cated. A set of formulas for calculating volume of symmetric compression chamber and gas forces in it is offered. The no-mal-equidistant-curve method and above formulas could be applied in scroll compressor design and its performance opti-mization.

Key words: Equation, Generatrix, Normal-equidistant-curve method, Profile, Scroll compressor